Here are the answers to some of the most frequently asked questions: 

Question 1:
According to ICAO, what do liquids, aerosols and gels (LAGs) comprise?
LAGs include, but are not limited to, the following items: water and other drinks, soups, syrups, jams, stews, sauces and pastes; foods in sauces or containing a high liquid content; creams, lotions, cosmetics and oils; perfumes; sprays; gels, including hair and shower gels; contents of pressurized containers, including shaving foam, other foam and deodorants; pastes, including toothpaste; liquid-solid mixtures; mascara; lip gloss or lip balm; and any other item of similar consistency at room temperature.
Question 2:
Which crew members are exempted from the LAGs restrictions stipulated in State letter AS 8/11-07/26 Confidential, dated 30 March 2007?
Paragraph 1.1 f) mentions "flight crew in uniform and on duty". For the purposes of these restrictions, flight crew compartment crew and cabin crew on duty the day(s) of the journey should be considered as eligible for exemption. Please note that paragraph 2.3.1 of this State letter offers flexibility for national authorities to exempt other categories of personnel.
Question 3:
Known supplier concept for LAGs and Security Tamper-evident Bags (STEBs): Who is concerned?
Appropriate Authorities and/or airport operators should approve "known suppliers" of LAGs and STEBs. All suppliers of LAGs to passengers are concerned and may become "known suppliers of LAGs", including duty-free shops, restaurants and snack bars, as well as airlines. All manufacturers of STEBs are obliged to implement the technical specifications contained in ICAO State letters and may become "known suppliers of STEBs" if, and only if, they are distributing their STEBs directly to "known suppliers of LAGs". All distributors of STEBs should become known suppliers of STEBs regardless of their production capabilities, and should take full responsibility of the security supply chain.
Question 4:
LAGs and STEBs: Which authorities should be contacted?
Civil aviation contacts are available at:​. For airport operators and airlines, please use local contacts.
Question 5:
Should STEBs be used for all duty-free goods?
No, STEBs should be used for transfer LAGs only, and not for any other goods purchased at duty-free shops, in order to simplify visual inspections at transfer airports. For LAGs not meant for transfers, normal plastic bags or low-level security bags may be used. The percentage of transfer passengers ranges from 10 to 50 per cent, with an average estimated around 25 to 30 per cent. It is essential to calculate the percentage of departing passengers who will transfer during their journey to estimate the percentage of STEBs required at departing airports.
Question 6:
Are all STEBs good for security?
All STEBs should strictly follow the technical specifications contained in State letter AS 8/11-07/26 Confidential, dated 30 March 2007. One of the most important purposes of STEBs is tamper-evidence. This means that only STEBs that meet ICAO specifications and are truly tamper-evident, regardless of the method of attempted infiltration, may be considered as STEBs that are "good for security". Harmonization of STEBs is also essential for security controls, as well as staff training.
Question 7:
Are STEBs sufficient for transfer passengers?
STEBs are only one component of the overall security system for LAGs, which should include measures for manufacturers, warehouses and airport retailers. A harmonized validation process between States is presented in State letter AS 8/11-07/53 Confidential, dated 6 July 2007. It should be noted that the European Commission has adopted a regulation on the validation process (number 915/2007, dated 31 July 2007), consistent with ICAO State letters.
Question 8:
Why should STEBs manufacturers register with ICAO?
State Letter AS 8/11-07/26, dated 30 March 2007, requests the registration of STEBs manufacturers with ICAO, in order that a unique identification code may be provided for each. The purpose of this measure is to:
1) obtain a centralized list of STEBs manufacturers for the use of States and industry stakeholders;
2) speed up the reporting process of any problem identified with STEBs (during a journey or elsewhere) to Appropriate Authorities and manufacturers of STEBs; and
3) consider further enhancements related to STEBs, either in their design, production or application of additional security devices, with the involvement of manufacturers.
Please note that only manufacturers may use their name in the "State/Manufacturer" box, not distributors.
Question 9:
Why should STEBs have inventory codes and security devices?
As with any other goods sold at shops, it is essential to use inventory codes in order to manage the stock of STEBs at retailers to ensure that no empty STEBs have been stolen or mishandled. It is recommended that STEBs inventory codes be scanned during sale so that stocks of STEBs at shops may be carefully managed.
Security devices are recommended in order to ensure proper security controls over the supply chain process. No specific technology is advocated, in order to leave all options open, including unique numbering, two dimensional bar codes, radio-frequency identification chips, etc.
Question 10:
Why should STEBs indicate a State three-letter code?
STEBs should indicate a State three-letter code in order to ease security controls at transfer points, by being able to readily determine the point of origin of the STEBs. State three-letter codes should be those used in  ICAO Doc 9303 — Machine Readable Travel Documents (available at: Please note that State three-letter codes are to be replaced by airline three-letter codes when LAGs are distributed on board. If the airport name is required, an additional box should be printed on the STEBs. The name of the manufacturer (not the distributor) should also be displayed.